NEARSIGHTEDNESS (MYOPIA)

Nearsightedness, medically termed as myopia, is a common vision condition affecting millions worldwide. It is a prevalent vision condition where distant objects appear blurry while close-up objects remain clear. It’s typically correctable with eyeglasses, contact lenses, or surgery.

Causes of Nearsightedness

The primary cause of myopia lies in the structure of the eye. Nearsightedness occurs when the eyeball is too long or the cornea is overly curved, light entering the eye doesn’t focus directly on the retina but in front of it, resulting in blurred vision for distant objects. This optical misalignment is termed a refractive error.

Prevalence of Myopia

Myopia is increasingly prevalent globally, with its occurrence notably higher in urban areas and among individuals engaged in extensive near work, such as reading or computer use.

Types of Myopia

Myopia, commonly known as nearsightedness, manifests in two main forms: non-pathological (simple or school myopia) and pathological (degenerative or malignant myopia).

1. Simple or School Myopia (Non-pathological):

Onset: Typically begins during childhood or adolescence.
Progression: Vision tends to stabilize after adolescence without worsening.
Correction: Correctable with eyeglasses or contact lenses to restore clear vision.

2. Degenerative or Malignant Myopia (Pathological):

Also Known As: Pathological or malignant myopia.
Inheritance: Often inherited from parents.
Onset: Develops rapidly, leading to severe myopia, usually during teenage or early adult years.
Progression: Can worsen significantly into adulthood.
Complications: Associated with various eye complications such as detached retina, choroid neovascularization (abnormal blood vessel growth in the eye), and glaucoma. It is a common cause of legal blindness.
Severity: More severe than simple myopia, with corrective lenses potentially inadequate for clear vision.

Symptoms of Degenerative Myopia:

Blind Spots: In central vision.
Wavy Lines: Straight lines may appear distorted.
Difficulty with Tasks: Everyday activities may become challenging due to distorted vision.
Contrast Issues: Difficulty perceiving contrasts in vision.

Bilateral Myopia: Myopia can affect one or both eyes. Bilateral myopia refers to nearsightedness in both eyes, a term used by eye care professionals to denote the condition’s occurrence in both eyes.

Symptoms of Myopia

While some individuals with myopia may not experience noticeable symptoms other than blurred distance vision, common symptoms include:

Headaches
Squinting
Eye Strain
Fatigue: Particularly when attempting to focus on distant objects for an extended period.

Signs in Children: Children with myopia may exhibit specific behaviors indicative of vision impairment, such as:

Squinting Frequently
Limited Awareness of Distant Objects
Excessive Blinking
Eye Rubbing
Proximity to Screens: Sitting unusually close to screens or having difficulty reading distant classroom materials.

Risk Factors for Nearsightedness

Several factors increase the likelihood of developing myopia:

Family History: Having a parent with myopia elevates the risk, with higher risks if both parents are affected.
Close-Up Activities: Prolonged engagement in tasks requiring close-up focus, like reading or detailed work, heightens the risk.
Screen Time: Extended screen use, particularly among children, is associated with a higher risk of myopia..
Age: Myopia often develops during childhood and adolescence, stabilizing in early adulthood.

Diagnosis of Myopia

An optometrist or ophthalmologist can diagnose myopia through a comprehensive eye examination, which may include:

Visual Acuity Test: This test assesses how well you can see objects at a distance. You’ll be asked to read letters or symbols on a chart, such as a Snellen chart, from a specific distance.
Phoropter Test: During this exam, you’ll look through a device called a phoropter while your doctor adjusts different lenses to find the prescription that provides you with the clearest vision.
Refraction Test: This test helps determine the specific refractive error of your eyes, which indicates the strength of lenses needed to correct your vision.
Retinal Examination: Your eye doctor may perform a retinal examination to assess the health of your retina and optic nerve.
Measurement of Eye Length: In some cases, your eye doctor may measure the length of your eyes to assess their shape and determine the degree of myopia.

Treatments for Nearsightedness

Myopia can be corrected through various methods, including:

Prescription Lenses:

Eyeglasses: Concave lenses are commonly prescribed for myopia. High-index lenses may be recommended for higher prescriptions.
Contact Lenses: Rigid gas-permeable or soft contact lenses are options for correcting myopia. Proper fitting is crucial, and dry eyes may limit suitability.

Surgical Interventions:

Photorefractive Keratectomy (PRK): A laser is used to reshape the cornea, allowing light to focus properly on the retina.
LASIK (Laser-Assisted In Situ Keratomileusis): A flap is created on the cornea’s surface, which is then reshaped using a laser, and the flap is replaced.
EVO Implantable Collamer Lens (ICL): A lens is implanted between the natural lens and iris to refract light onto the retina, providing clearer vision.

Management of High Myopia:

Special Contacts: Special contact lenses or atropine eyedrops can help slow the progression of high myopia.
Surgery: In some cases, cataract or clear lens replacement surgery may be recommended.

Home Care Tips for Myopia

Take frequent breaks during prolonged near work to reduce eye strain.
Ensure proper lighting when reading or using electronic devices.
Follow the prescribed eyewear regimen to maintain optimal vision.
Monitor your vision and update prescriptions as needed.

Prevention of Nearsightedness

While some risk factors for myopia, such as genetics, cannot be controlled, preventive measures include:

Encouraging outdoor activities, as natural light exposure may help reduce the risk of myopia.
Limiting screen time, especially for children, and implementing the 20-20-20 rule (every 20 minutes, look at something 20 feet away for at least 20 seconds).
Overall Health: Maintain a healthy lifestyle with balanced nutrition, regular exercise, and avoidance of smoking.
Use protective glasses to prevent injuries while correcting vision during sports.
Wear sunglasses and seek shade to shield your eyes from harmful UV rays.

Myopia Complications

Untreated myopia can lead to various complications, including:

Academic Struggles: Uncorrected myopia in children may affect academic performance.
Reduced Quality of Life: Vision impairment can hinder daily activities and social interactions.
Eyestrain: Straining to see can cause fatigue and headaches.
Safety Concerns: Impaired vision poses risks during activities like driving and operating machinery.
Eye Health Issues: Severe myopia increases the risk of retinal detachment, glaucoma, and cataracts.

Myopia vs. Hyperopia

Myopia (Nearsightedness):

Definition: Myopia refers to nearsightedness, where distant objects appear blurry while close objects remain clear.
Prevalence: It is a common refractive error, more prevalent than hyperopia.
Correction: Corrected with concave lenses, which focus light directly onto the retina.

Hyperopia (Farsightedness):

Definition: Hyperopia denotes farsightedness, where distant objects are clear but close objects appear blurry.
Prevalence: Less common than myopia.
Correction: Requires convex lenses, which help converge light rays onto the retina.

Myopia and Astigmatism

Astigmatism:

Description: Astigmatism results from an irregularly shaped cornea or lens, causing blurry vision both near and far.
Correction: Corrected with cylindrical lenses, which compensate for the irregular shape of the eye.

Highest Myopia

Measurement: Refractive errors are measured in diopters (D), with negative values indicating myopia.
Classification:
- Mild Myopia: Up to -1.5 D.
- Severe Myopia: -1.5 D to -6.0 D.
- High Myopia: Above -6.0 D.
- Pathological Myopia: Exceeds -8.0 D, associated with increased risk of complications such as retinal detachment and glaucoma.

FAQs

Can Myopia be Cured?

Myopia is not curable, but treatments such as LASIK and other surgical interventions can effectively restore vision. However, they do not offer permanent solutions, and additional vision correction may be needed with age.

How can you cure myopia naturally and effectively?

Myopia cannot be cured naturally, but you can effectively manage it with proper eye care. Regular visits to your eye doctor, adherence to your treatment plan (such as wearing corrective lenses or undergoing surgery if recommended), and practicing good eye health habits like taking breaks from screens, maintaining a healthy lifestyle, and using eye protection can help maintain clear vision.

When to See a Doctor

Consult an eye care professional if you experience sudden vision changes, such as floaters, flashes of light, or vision obstruction.

Regular eye exams are crucial for detecting and managing myopia. Here’s when to schedule appointments:

Children: Screen vision yearly from birth through adolescence.
20s: Have an eye exam once.
30s: Two eye exams.
40s: Comprehensive eye exam. Follow your eye doctor’s recommendations for future screenings.
65+: Annual or biennial eye exams.

Outlook and Prognosis

Progression: Myopia often starts in childhood and may stabilize by the teenage years. However, cases of myopia have been increasing, necessitating regular eye check-ups and interventions to manage progression.
Preventive Measures: Multifocal lenses and certain eye drops can help slow myopia progression. Regular monitoring by an eye doctor is essential for timely intervention.

With appropriate correction, myopia typically does not lead to severe complications. However, regular eye examinations are essential to monitor vision changes and adjust treatment accordingly.

Sources:

American Academy of Ophthalmology. “Myopia (Nearsightedness).” Aao.org.
National Eye Institute. “Facts About Myopia.” Nei.nih.gov.
Mayo Clinic. “Nearsightedness (Myopia).” Mayoclinic.org.
American Optometric Association. “Myopia (Nearsightedness).” Aoa.org.
World Health Organization. “The Impact of Myopia and High Myopia.” Who.int.
National Institutes of Health. “Genetics of Myopia.” Nih.gov.
The Vision Council. “Digital Eye Strain Report.” Thevisioncouncil.org.

MYOPIA NEARSIGHTEDNESS